Maou Gakuin No Futekigousha - Chapter 17: Necron sisters

Due to an unexpected turn of events, Xia Fei consumed a Super Gene Optimization Fluid that bore no brand, expiry date, instructions or stated its place of origin.
Our story begins here…

Du Fei was reborn, and in this difficult era of extreme shortage of supplies, he started his wonderful life of opening and hanging…

- Description from novelbuddy

Six thousand years ago, Su Changsheng traveled through the fantasy world. He practiced hard and wanted to reach the peak, but he failed to even attain sainthood and was backlashed. He was disheartened, and when he wanted to die…The system was accidentally activated.‘As long as you marry a wife and have children, and develop the family, you can continue to get rewards and resources.’Su Changsheng suddenly realized the right way to advance to the peak.[You married Gu Qingge, the Empress of Destiny, and she gave birth to your first daughter. Talent: Indestructible Body, Aptitude: Peerless in the world!] [Rewards: Indestructible Body of the First Demon of All Calamities; Emperor-level Scripture!] [You vigorously developed the family and successfully promoted it to the ancient family!] [Rewards: Ancient Clan Gift Package; Luck-Golden Dragon; Imperial Weapon from Ancient Clan] [You married the Ancient Queen…] [You married Quintuplet Goddess from the Celestial Clan…]“I can have such achievements in my life, it’s all thanks to my own efforts!”Several years later, Su Changsheng, the supreme immortal master of the heavens, revered as the Great Heavenly Emperor Changsheng, humbled himself.

The Apocalypse is in full swing. Defiled - powerful creatures corrupted by the Great Collision - prowled the lands in search of prey. Unfortunately for them, the human race had long since retreated behind the secure walls of the Sanctuary of Everlast. During one of his regular excursions outside the Sanctuary, Alden is separated from Celeste. - his childhood friend and crush. In that moment, he came to regret never summoning the courage to confess. Somehow managing to survive thanks to some trickery, Alden awakens as a mage. Instead of receiving a normal power, he gains the ability to decay. What’s more, during his ascension, he received a vision from his future self advising him not to trust the Asterons - celestial beings who had saved his race from inescapable doom. Normally... such a revelation wouldn’t faze Alden. However, there was only one major problem with the declaration, though. Celeste was bound with an Asteron. And not just any normal Asteron... She had made a pact with one of the Divine Sovereigns.